Gem-polishing machine.



C. I. COLEMAN. GEN! POLISHING MACHINE. APPLICATION mm nov.2s. 1912.

Patented Feb. 29,1916.

(swans-shin 1.

Jaws:

C. J. COLEMAN. GEM POLISHING MAGHINE. APPLHIATEON FILED uov.25. 19:2.

Patented Feb. 29,1916.

4 SHETS SHEET 3.

0.1. COLEMAN. GEM pousnms MACHINE. APPLICATION FILED NOV.25. I912.

1,173,175. Patented Feb. 29, 1916 4 saints-sneer].

[Ji /a Ely/1.

UNITED STATES PATENT OFFICE.

CLYDE J. COLEMAN, OF NEW ROCHELLE rhlI EW YORK, ASSIGNOR, BY MESNE ASSIGIL MENTS, T0 STERN-COLEMAN DIjAMOND MACHINE CbMPANY, INC., A CORPORATION OF NEW YORK.

cnm-romsnmc Miitnmn Patented Feb. 29, 1916.

Application filed November 25, 1912. Serial No. 733,422.

part thereof.

My invention relates to machines f0 grinding and polishing diamonds and other gems, and general ob ects of my invention are accuracy, celerity and reliability of operation, facility of manipulation and simplicity, rigidity and durability of construction.

A more specific object of my invention is to provide a device wher eby facets oFvag iT rious areas may bepohshed with squat" celerity.

Another object is to obviate skill and prevent scratching of the polishing lap in applying the gem to the lap.

Another object is to provide trippin devices for both a depth gage mechanism and a reciprocatory mechanism, which will be op erated by engaging the lap and which will be so arranged that they will not be difierentially effected from the gem by unevennesses upon the lap.

Another object is to provide for easy and convenient disengagement of the gem-holding head from its support.

Still other objects and advantages of my invention will appear from the following description.

My invention comprehends variable pressure-applying means arranged to press the gem against the lap with a force increasing in proportion to the increase in ea (if the facet as the gem' is polished, and 'cifically comprising weighted levers connecting the supporting spindle for the dop-holding head with the spindle-supporting member and operative to rotate from a vertical position asthe gem is polished oli', thereby applying pressure to draw the spindle down through its support toward the lap.

My invention further comprehends a check device, specifically a dash pot, ar-

ranged to check the rapidity of movement of the gem toward the lap, thereby obviating skill in applying the gem to the lap.

My. invention also comprehends the arrangement of a depth-gage trigger and a reciprocatory-means-operating trigger in radial alinement, or side by side, so that both {nay track in the path of the gem upon the My invention also comprehends an angularly movable support for these triggers, ad-

justable angularly about the gem-holding end to bring the triggers into tracking aline with the gem, and a spring clamp fricfii gna'lly clamping the trigger support to the gem-holding head and including a pointer cooperating with an index carried ythe gem-holding head.

My invention comprehends various other features of construction, and arrangements -and combinations of parts, as will hereinafter more fully appear.

I shall now describe the embodiment of my invention illustrated in the accompanying drawings, and shall thereafter point out my invention in claims.

Figure 1 is a side elevation of a complete machine embodying my invention, with the supporting table in section and the lap p tially in section. ll same. Fig. 3 is an enlarged vertical section of the same on line 3-3 of Figs. 1 and 2 looking toward the left and showing the gem-holding head in side elcvati n with the dop-holding head broken off, the lap and table bein omitted. Fig. 4 is a detail in further enirged central section of the check device. Fig. 5 is a transverse section of the same on line 55 of Fig. 4, looking down. Fig. 6 is a transverse section of e same on line 66 of Fig. 4, looking up. lg. 7 is an elevation partly in vertical section of the gem holding head, drawn to the scale of Fig. 3. Fig. 8 is a transverse section of the same on line 88 of Fig. 7, looking down. Fig. 9 is a transverse section of the same on line 99 of Fig. 7, looking up. Figs. 10 and 11 are, respectively, a plan and a side elevation of the index plate. Figs. 12 and 13are, respectively, a plan and side elevation of the spring clamp.

The illustrated embodiment of my inven: tion has a disk shapedrotative lap 1 rigidly mounted u on a vertical shaft 2, Which bears in the to. le 3 of the machine and to which power is applied in any suitable way. The upper or the polishing surface of the lap is coated with diamond dust or other suitable abrasive, as is usual.

To hold the gem 4 which is being polished in contact with the polishing surface of the lap 1, adop-holding head isprovided on the lower of a vertical spindle 5. This supporting s indle is crooked at its lower end to p'i'ovi e a horizontally extending supporting arm on which is provided a slotted arcuate supporting guide 6 for the dop-holding head in a vertical plane coincident with the axis of the spindle 5, arranged to support the dop-holding head upon the upper side of this arcuate guide. This guide has its center coincident with the geometric center of the gem and disposed in the axial line of the spindle 5,and this feature embodies my invention described and claimed in my copending application Serial Number 733,417, filed on even date herewith.

The dop consists of a tubular spindle portion 7 and an enlarged tapereddop head 8 provided with a longitudinal bore for receiving the gem arbor 9. This arbor is provided with a longitudinal slot, as shown in Fig. 7, and a set screw 10 in the-dop head is arranged to screw into this slot and hold the arbor against relative rotation. A sleeve member 11 surrounds the dop spindle 7 and extends downwardly through the slotted arcuate guide 6,and this sleeve member is provided with an enlarged index head 12, the under side of which is shaped to engage the guide faces of the arcuate guide 6, the engaging faces being preferably Vshaped as shown. A clamp nut 13 on the sleeve member 11 screws underneath the guide 6 and clamps the sleeve member to the guide, a washer 14 being interposed between the nut and the guide. To the upper end ofthe spindle 7 is clamped a latch member 15 arranged to engage in calibrated notches 16 in the upper edge of the index head 12, and this latch member may be raised manually and turned to any angle, thereby turning the gem axially to present different facets to the lap, and a flat spring 17 returns the latch to locking engagement with the notch 16 to which the latch is adjusted. A drift pin may be inserted down through the bore in the spindle 7 to remove the arbor from the dop.

The vertical supporting spindle 5 is mounted for free longitudinal movement within certain limits. as will hereinafter ap pear, in a spindle supporting block 18, which has an overhanging portion 1 provided with a rounded under side adapted tn fit upon an intermediate supporting block 20 having a rounded longitudinal upper edge. This intermediate supporting block 20 is supported upon and has a dovetail engagement with a transversely extending supporting arm 21, which is supported upon the standard 62 at the outer edge of the table 3, as shown in Fig. 1; The intermediate supporting block 20 is, therefore, free to move longitudinally of the supportingarm 21, whlle the spindle-supporting block 18 is free to move longitudinally of the intermediate supporting block 20 and is supported thereon by the overhanging portion 19, and, since the vertical engaging faces of the two members are of substantial length, the spindle-supporting block 18 will be held firmly by gravity to the intermediate sup porting block. The intermediate supporting block is provided near its bottom with a serrated plate 22 having serrations on its under side, and the spindle-supporting block 18 is provided on each side with a plate 23 having a projecting tooth 24 arranged to engage in the serrations in the plate on the intermediate supporting member 20.

The rounded engaging faces between the overhanging portion 19 and the intermediate supporting block 21 permit the gemholding head to be readily rocked out *from the intermediate supporting block and lifted off its support or adjusted longitudinally of the supporting block, the tooth 24 serving to lock the gem-holding head in adjusted position. In the machin'e shown, the supporting arm 21 extends parallel to the radial line on the lap 1 occupied by the gem 4, and in the movement of the spindle-supporting block 18 along the intermediate block 20 on the supporting arm, the gem 4 is guided in a radial line transversely of the lap. The spindle 5 is normally held by gravity with the gem resting upon the polishing surface of the lap in the position shown in the drawings, and it, therefore, falls down with the gem as the gem is polished 011, being free to mov longitudinally V away from the lap.

To prevent, the gem from being polished to too great a depth at any facet, auto matic disengaging means are provided, which become operative at the conclusion of the polishing operation upon every facet and the illustrated tripping mechanism for this purpose is an embodiment of my invention described and claimed in my ropending application, Serial Number 733,418, filed on even date herewith. This disengaging mechanism consists of means for raising the gem holder and gem away from the lap and a trigger for operating this mechanism. which is arranged in the pathof the cm upon the lap and is so adjusted that it .rikes the lap at a predetermined stageof the polishing operation and is tripped thereby and operates the disengaging mechanism.

ing cup 13:1 surround the spin integrrii with nnorouieter owned. at its upper end. which ith threads on the spindle 5 uppw end. the upper i-nd of the :1 3,1 fiillliiik ring eaiibratcd. as shown, to indic: z the adjustment of the micrlnneter screw !:lia- .m1pingoverthc inner spring cup and :nrsngml rcversely thereto is an outer 1 c p ."3- and a roiied thrust spring eminds the spindie iii. and bears at its and :igzinet the top i the stationary a.=.= cup 23.. nnd at its lower end against the b ittom of the slidalde outer cup 26. and tends in spur-ad ti. 5 cup apart until the button: of the cup it} strikes an abutment nut :28 on the screw-thrcaded upper end of the spindle-supporting block 18, and then the further separation of the cups raises the spimile 5 far as the crooked lower end of the s indle 3 will permit. The Art r 'd iiifah. cup is. however, normally in hed the tension of the spring 27 by a series; of irvers, comprising a latch {ever :25). a locking lever 3!) and a depthgage tri ger- '25]. To support these levers. a L shsped icycr-supporting member 32 is pro arranged with its legs horizontal and its base vertical. as shown, and its upper bag is split and provided with a split cir cular o 'ieniug arranged to be clamped by clamp screws 33 about the micrometer screw 26. \lhr engaging face of the circular clamp b ing if oped and fitting into a. periph oral g oove of oi-responding shape in the micrometer or thereby securely clamp ing the two 32:: togeth r against relative idinally of the spindle 5 relative rotational movement between the two members. The lower ieg of the lcvensupporting member 32 is somewhat iougger than the upper leg and 1s pivoted. upon rho spindle 5 siightlv above the crooked lower end. being split and oped s rews 31 similar to the ("lampwiction oi the other The leverm- :dier is thu supported on idle I? :it two point iieientiy far :i;.. rigidly hold the havens:ipporting member in parallelism with the spindle. The base portion of the lever-supporting member is channeled and is provided near its bottom with a. lug 35. and the inner end oi the locking lever is bifurcated and struddles this lug 35 and is pivoted thereto. This locking lever 30 extends rearwardly tbrc' ugh a slot in the bottom. of the spindlesupporting block 18. as shown in Fig. 7. The latch ir-ver 99 is pivoted at its lower rod to the inching lever 30 near its inner end and extends verticaliy For the greater portion of its length within the channeled so of the love upporting member and idcd near its upper end by a guide 36 .iling outwardly from the base of the channel portion. The latch lever 29 is bent inwardly near its upper end and its end is tiu'ned upwardly and is arranged to latch under a flange 37 on a slidable cup member 26. The depth-gage trigger 31 is pivoted at its upper end to the free end of the lower leg of the lever-supporting member 32 and extends down toward the lap and is provided with a locking nose 38 arranged to rest under the downwardly projecting free end of the looking lever 30 and prevents the free end from being forced down and there by holds the latch lever 29 in locked position and prevents the separation of the two spring cups 25 and 26. 'hen the trigger 31 is rocked upon its pivot, the nose 38 is moved from under the locking lever 30 and the latch lever 29 is therefore free to force down by the tension of the spring 27, and the spring thereupon becomes effective to separate the two cup members and raise the spiniflle 5 and disengage the gem from the lap. This rocking of the trigger 31 upon its pivot is efl'ected by the engagement of the lower end of the trigger with the lap. the engaging end of the trigger being made arcuate concentric with its pivot so that the trigger is merely rotated and it is pivoted without any tendency to move its pivoted and connected parts. The trigger 31 is arranged to engage the lap at a predetermined time, and thereby determine the depth to whicha facet will be )olished, and this time of disengagement o the gem by the operation of the trigger 31 is determined by adjusting the micrometer screw longitudinally of the spindle 5, thereby moving the lever-supporting member 32 and the trigger 31 toward and from the lap to the desired'adjusted position.

The trigger 31 is arranged so that it engages the latch directly behind the gem. as shown, so that it will engage precisely the same path upon the lap that the gem does, and the two will not be differentially affected by unevenncsses upon the lap. To adjust the trigger angulariy about the gem to bring it into tracking alincment, the lcvensupporting member 32 is adjusted upon its pivot angularly about the spindle 5. To hold the lever-supporting member 32 in adjusted position, a spring clamp 39 is provided. This spring clamp is bifurcated and its bifurcated portion surrounds the spindle 5 about an undercut collar portion 40 (see Fig. 3) and at its opposite end the spring clamp 39 is provided with two upwardly projecting fingers 41, which straddle the lower leg of the lever-supporting member 32. This spring clamp 39 is, therefore. locked against movement relative to the lever-supporting member 32, and it engages the collar 40 with sufficient friction to hold the lever-supporting member in adjusted position. To indicate the position of adiustment. a pointer 49 is provided on the spring clamp which cooperates with a calibrated index plate l3 lixed on the spindle .3 directly above the collar 40. The intermediate supporting block 20 is also eorrespondinglv calibrated. and as the gem-holding head adjusted longitudinally of the interim-diate supporting block 20, the triogger 31 is adjusted until the indication on the index l3 corresponds to the indication on the intermediate supporting block 20, and the trigger is then in tracking alinement with the gem.

To preve t unevennesses on the polishing surfaces of he lap from producing streaks or grooves in the facets of the gem, I provide means for reciprocatingthe gem transversel ot' the lap which are normally inoperative and which are thrown into operation near the end of the polishing operation. and these means embody my invention claimed and described in my COPEWIllHE applieation Serial Number 733317, filed on even date herewith. The illustrated means comprise an electric motor 4 mounted upon a rearward extension of the supporting arm 2L which operates a worm wheel 45, on the shaft of which is provided a crank 46 con nectcd by a pitman 47 with the intermediate supporting block 20. and when this motor is energized. the intermediate supporting block 20. and conseepientlv the gem holder and gem, are reciprocated longitudinally of the supporting arm 21 through this motordriven means. Supported upon laterallv extending arms projecting! from the supporting arm "21 is a stationary contact member 48 extending parallel with the supporting arm 21 and of a length substantially equal to that of the supporting block 20. these laterally extending arms. to which the stationary contact 49 is secured. being insulated from the supporting arm 21. as shown in Fig. 3. A movable cooperating spring contact member 49 is carried by the lower leg of the lQVGP-SIlPPOlTtlUfI member 32 in position to make contact with the stationary member in anv position of adjustment of the gem-holding head. \Vhen this movable coir tact member all) contacts with its cooper atingz Contact member 48, the motor circuit is. completed as follows: from the battery 50, through wire 51, stationary contact 48. movable t'Ofitaet 4'9 and frame of the machine to wire 52 and the field coils of the motor and wire 53 back to the battery 50. This spring contact 49 is, however, normallv h ld away from its cooperating contact by a contact-controlling trigger :i-l. 'also pivoted to the free end of the lower leg of the levee supporting member by the side of or in radial alinement with the depth-gage trigger 31. the two triggers beingthin and so close together that the contact-controlling trigger also engages the lap in the path of the gem so that it is not differentially all'eeted from the gem by uneveuoesscs upon the lap This contact lever 54: is provided on its upper end with a disengaging nose arranged so that, in the normal position of the contact-controlling lever 5'14, this nose engages underneath the spring; contact 4.) and holds it away from its clamping contact, as shown in Fig. 3. As the (:ontactrom trolling trigger :34 engages the lap and is rocked upon its pivot, this nose 5% is removed so that the spring; contact is free to close the electric contact and energize the motor. This contaet-rontrolling trigger 54 is slightly longer than the deptlrgage trigger 3L so that it engages the lap andinitiatea the operation of the reeiprocatory inerlne nism a short time before the trigger 31 is tri )ped and the gem lifted from the lapa s previously stated. the gem is held rv gravity against the lap when the diewnga ing mechanism is locked. At the beginning of the polishing operation only a point or a relatively small surface is presented to the lap hut as the facet polished down this area becomes larger and the surface to he polished therefore continually increases dur ing the polishing operation. In' order that the facet may be polished with equal rapid ity as the area of the facet increases. 1 provide variable pressure means which serve to assist gravity in pressing the gem strait the lap. and exert progressively incre 1 pressure upon the gem as it is pt'ilished down. These means in the illustrated cor bodiment comprise two weighted hell-cram: levers 5G pivoted to opposite sides of th spindle-supporting hloclt 18. and conneried by coupling links It? to radially extending arms 58 on a collar 59 clamped about the micrometer screw E36 just above the upper leg of the lever-supporting menihrr IE2 These levers tend to rotate from a vert toward a horizontal position and lh re draw the micrometer srrmv J l and it. the spindle 5, down through the spindle supporting block 15. and they thereby ert force to press the gem forward against the lap with'increasiug pressure as they roe tate from the vertical position. the part are so designed that when the gem is first applied to the lap. the spindle is held up in its supporting hloclt to such a position that the weighted levers .36 are substantially \el tical and the leve s. then-fore exert, a mini mum of pressure when the surface at the facet is smallest. As the faret is polished down. the levers 56 rotate toward the h rizontal. and sine-e the pressure which they exert increases in proportion to their angle from the vertical, the pressure whirh they" exert upon the gem increases as the gem s i'lOllSl'ltltl oil and in proportion to the incteasein area of the facet. The arhors are made of'variahledongths according to the sizs of, and thcy are so designed that the facet po ished is always the same distance H1911; t e end of tilt lop. irrespective of tin; size of the gem. (hmsm'picntly the Wrigh 's: so are always in a vurtical posit m at the bcgiunmg of the angers.- tion, irrcs aativc of the size of the gem.

To limit the upward movement of the spindle 5 and connected parts relative to the spindlesupporting member 18, the inner spring cup is providcd'with two diametrically opposite downwardly cxtcndin r [ingers or projections which project own through slots provided for them in the bottom of the inter sliilable paring cup 26 an r Md of these proicctions fifi is rounded .w e' gar-ideal. viz-3 op nnt 61 arranges} w Ul'fibi a shoulder on the bntmh nut 25* and thereby limit the :11 d mmement of the spindie 5. As

the gen; polished oil and the spindle moved dmvn through its support, these stop nuts ii more away from the shoulder on the alums-aw? not. and the parts are so arranged that {he i; is lsctween the bottom of the sliiluble cup 13 and the top of the abutment nut is aisays the same when the depth gage trigger 31 is tripped.

Tu prevent scratching of the la when the gem is first presented to the ap, which will result if the gem is pressed too hard against the lap at the bcginning'of the polishing operation when a point of the gem is presented to the lap, a check device is pro vided for checking the ra'gjiidity of movement of the gem toward the lap. In the illustrated machi this hm-l; device comprises a dash not i. r. cl meat of which is connect-ad to our l 1 his}, hell-crank irw 36 and of which is sciu i side of the sp dash pot i; mg g lirv hi sill not spill out in any position in which the head is j (a cymller or? in WhNl] telescopes the falvcczzl' cylinder 11%. the two being flexibic lujn l tight cover 65: s: oi the inner nmial -le tel scoping slut-i al by a d: mvaniiy opening "a ill'l! is laid :ar the seat by a ia-us u the tension us spring \vliei the ibis elenwnt is raisci'l. thereby permittin "a movement of the ffliiii! away from the As the mov abie clement 5% moves i he opposite riier. the valve (it; is closed and movement is retarded. a integral with a winged to guidc the valvrn and .1 with a restricted central 581 communihating with three late -ts (29. A. screw plug '50 in the b0 1 of the valve 66 is providcd with a g.OiH8 which taaumunicatcs with longiluriiual ed. The lower stationary member com It is obvious that various modifications may be made in the.constructi0n shown in the drawings and above particularly described within the principle and scope of my invention.

I claim:

1. A gem olishing machine comprising a polishing lllp, a dop-h0lding head arranged to hold :1 cm in engagement with the lap, and varlable pressure-applying means arranged to press the gem against the lap with progressively increasing pressure as a facet is polished.

2. A. gem polishing machine comprising a polishing lap, a dop-holding head arranged tohold a gem in engagement with the lap, a spindle carrying the dop-holding head and arranged for free axial movement toward and from the lap, and variable ressurc-applying means engaging the spindle and arranged to press the spindle axially toward the lap with progressively increasing pressure as a facet is polished.

3. A gem polishing machine comprising a polishing lap, a dop-holding head arranged to hold 9 gem in engagement with the lap, a.spindle-sapporting member, a spindle carrying the (lop-holding head and mounted in the spindle-supporting member for free axial movement toward and from the lap, and a weighted lever operatively connected to the spindle and spindle-supporting member and arranged to gravitate from a vertical toward a horizontal position as a facet is polished and thereby press the spindle axially toward the lap with progressively increasing pressure.

l. A gem polishing machine comprising a polishing lap, a (lop-holding head arranged to hold a gem in engagement with the lap, a spindle-supporting member, a spindle car; rying the (lop-holding head and mounted in the spindle-supporting member for free axial movement toward and from the lap, and a weighted lever stationarily pivoted on the spindle-supporting member, a link cou. pling the lever to the spindle, the lever bemg arranged to rotate about its pivot from a ertical position and draw the spindle through its supporting member toward the lap, thereby applying progressively increasing ressure upon the gem as a facet is polished 5. A gem polishing machine comprising a polishing lap, a (lop-holding head arranged arranged in control of the diseng to hold a gem in engagement with the lap, variable pressnre-applying means arranged to press the gem against the lap with progressively increasing pressure as a facet is polished, and a check device operative to control the apidity of the movement of the gem toward the lap.

EMA gen: polishing machine conrprising a. polishing lay a drip-holding hear arranged to hold a gem in engagement with the lap, a spindle-supporting member, a spindle carrying the dop-holding head and mounted in the spitulle-supporting member for free axial mmenient toward and from the lap. a \ieighted lerer pivotally mounted on the spindle'snpporting member and coupled to the spindle and arranged to rotate about its pi\ ot from a vertical position and draw the spindle through its supporting member toward the lap, thereby applying progressively increasing pressure upon the gem as a facet is polished. and a check de vice operative to control the rapidity of the movement of the gem toward the lap.

7. A gem polishing machine comprising a relatively rotary lap a gem holder arranged to hold a gem in contact with the lap and to approach the lap as the gem is polished, disengaging means arranged when operated to lift the holder from the lap. a depth-gage trigger carried by the holder in the path of the gem upon the lap and aging means and adapted to engage the lap at a predetermined stage of the polishing oper ation and to be operated thereby to operate the disengaging means, normally inoper ative reciproeatory means adapted to reciprocate the gem holder across the lap, and a reoiprocatorr-n1eans-operating trigger arranged to engage the lap in the path of the gem in radial alinenient with the depthgage trigger and to be operated thereby to render the reciproratory means operative.

8. & gem polishing machine comprising a relatively rotary lap a gem holder arranged to hold a gem in contact with the lap and to approach the lap as the gem is polished. disengaging means arranged when operated to lift the holder from the lap. a dcptlegage trigger rarried by the holder in the path of the gem upon the lap and arranged in control n? the disengaging means and adapted to engage the lap at a predetermined stage of the polishing operation and to be operated thereby to operate the disengaging means, a normally del nergized eleutrin motor operatirely connected to reciprocate the holder across the lap. a contact-coutrolling trigger arranged to en-- gage the lap in the path of the gem in radial alinement with the depth-gage trigger and to he rocked. thereby at a predetermincd state of the polishing operation and normally open electric contacts for the uann motor arranged to la: rinsed b; the. rocking eontrolling trigger and to of the eonta therehy energme the electric motor,

Q. A gem polishing machine romprising a relatively rotary lap, a. gem holder arranged to hold a gem in content with the lap, an elertrir motor peratinely eonnretrd to reriprorate the holder :srmss the la n a source oi current therefor, a stationarxelectrir rontact, and a roiipcratire movable coir tart oarrird by lhe gent holder and arranged to make sliding ronrart with the stationa ronl n-l as the gem he hirr is reci i A gen; pol i a relatilrlr rotary Earn i rangrd to iilll a gem in rortart with the lap and to ap aroarl la' lap aa thrgem is l polished, an electric motor operatirely eon nrctrd to ittfiljf-Wliltl? the holder across the lap. a sourre ot rnrrrnt therefor a stationary elrrtrir rontart, a roilper:itzrr more e eon tact carried by the gem holder and arranged to make sliding rontaet with the stationarv rontart as the gran holder iroratrd and a ro'ntact-rontrolling t the grin holder and rel ali n lap at a predetermined ing operation and to l e operative to rlose th lm i H ll. A gem polishir z lnarliiinz rump-main" a relatively r t-arr iagn a grin iiw 'll' ranged to hold the gem in Contact with the lap and to approarh the lap as the in is polished, a supporting aria l'or tin holder extending transvei of the lap. an intermediate E-THPIJUILEEF hlorl; for the gem holder mounted upon the supporting arm for movement longiturlinallr thereof; the gem holder hring adjustable lanai-Adi nally of the supporting hlo ln an i 'zrilil ifi motor operatirel mnnwrted to rel i'UtCZilt? gem holder long the supporting ldoel; and tudinally of the supporting arnn a sin arr elerlrir rontnrt for the motor i extending substantially the length of the supporting blot-lg :1 rooperatire spring electrie contarl nnnahle with the supporting block and arranged to engage tliestationar'v ontact in any position of the snpporting lrltilli and aloe the motor rironit, and eonlllttnfhlfllj'tilling l2 r rarried by the gem holder and iniin'aallfv holding the spring rontart open and a r31 .ngrri to engage the lap at a predeternimaul stage ol? the polishing nperati on and to he operated therein to release the spring COHt'dCl. and close the motor rim-nit.

'l-J, It gen: polishing inarhine comprising a polishing lap, a genrholding head airranged to hold a gem in rontact with the lap. at supporting arm {or the gem-holding head provided with a serrated portion at its lower edge. and a lorlting tooth on the gennholding head arraw eil m engage the serrated portion l the supporting arm and All? lock the gem holding head against move ment longitudinally of the supporting arm, the engaging faces of the gem-hoiding head and supportingarm, being so shaped that the gem-holding head may be rocked upon the supporting arm to move the lot-king tooth out of engagement with the serrated portion and thereby release the gem-holding head from the supporting arm.

13. A gem polishing machine comprising a polishing lap, a gem holder arranged to hold a gem in contact with the lap and. to approach the lap as the gem is polished, disengaging means arranged when operated to lift the holder from the lap, a deg'ith-gage trigger arranged to engage the lap at a pro determined stage of the polishing operation. and to be operated thereby to operate the disengaging means, an angnlarly n'iovahle supporting member for the depthgage trig ger arranged to move the trigger angularly about the gem holder, a spring'clamp se cured to the angularly movable support and frietionally engaging the gem holder, a pointer on the spring clamp, and a coiiperative index on the holder cooperative with the pointer to indicate the angle of adjustment of the ilepth-gage trigger.

14. A gem polishing machine comprising a polishing lap, a (lop-holding head arranged to hold a gem in engagement with the lap, a spindle carrying the dopholding head and mounted for free axial movement toward and away from the lap, disengaging means operative to move the spindle and (lop-holding head away from the lap, 21 depth-gage trigger arranged to engage the lap at a predetermined stage of the polish ing operation. and to be operated thereby to operate the disengaging means, and a trigger-supporting member carried by the spindle and adjustable longitudinally thereof and guided thereby.

15. A gem polishing machine comprising a polishing lap, 21, dop-holding head ar ran ed to hold a gem in engagement with the ap, a spindle-holding member, a spin dle carrying the (lop-holding head and mounted on the spindle-holding member for free axial movement toward and away from the lap, disengaging means operative to move the spindle and (lop-holding head away from the lap, a depth-gage trigger arranged to engage the lap at a predetermined stage of the polishing operation and to be operated thereby to operate the disengaging means, and a U-shaped trigger-supporting yoke member adjustable longitudinally of the spindle and supported thereby at two points spaced by the spindle holding memher, so that these points of support are at a sutlicient distance apart to atl'ord a rigid guide for the trigger-supporting member.

-16. A gem polishing machine comprising a polishing lap, at (lop-holding head arranged to hold a gem in engagement with the tags a spindle veri ying the drip-holding head and mounted. for tree axiai movement toward and away from the lap, il engaging means operative to in are the spindle and dopliolding head away from the law a deptlrgage trigger arranged to engagithe lap at a predetermined stag of the poiish ing operation and to he operated thereby to operate the disengaging swarm a mirrome ter screw on the spindle having a V'shayaal peripheral bearing fare and a trigger-sun porting member carried by the micrometer screw and provided with a romplen'ient V-shaped annuiar am engaging the ripheral hearing [are of the HliiHm-m screw IT. A gen polishing machine \fl,l'll.till'i ill l a polishing lap. a drip-holding head ar ranged to hold a gem in engagement the lap, a spindle carrying the iloph head and mounted for free axial more toward and away from the lap, disen; g means operative to move the spindle and dop hohling head away from the lap. :11 a deptlrgage trigger arranged to engage the lap at predetermined stage of the polish ing operation and to he operated thi-r to operate the disengaging means. a mlCl'i-i'ili ter screw on the spindle having a J sliaped peripherai groovia a triggersupporting member rarried by the micrometer mreri and pritivii'led with a Vsliape l annuiar split clamp engaging in the periplwral groove of the micrometer screw and. r auipii for adjiistahly clamping the triggrr porting mmnher about the micrometer the trig e sup porting nienilier th rein, as ing arljiss i i a t the spiii-llr able ah lm'iy to bringthe trigger into the path a? the ma: upon the lap.

18. In a gem polishing Il'lfli'lililt, an ate 1 supp tmg guide slotted to worlds spahed side parts, and a dop holding timid. adjusta le upon the areuate guide 'nd win: prising a dr p, a sleeve member s ioitin lmr; the dop and extending through the ot in the arruat guide and provided with a head engaging upon one side of" the area-ate gulo, and a whooping nut surrounding the member at the other side of the a guide and oprratiw to clamp the sii'rw the areuate aider holdinghead for gem pol shing marl an arbor-holding dop pro vided with a tubular (lop head. a gear-holoing arbor in the dop head provided with a longituilinai groove a locking member in the (lop head arranged to engage in the 10m liliiii eove and hold the fitilm e. rotation, and me: tor ative adjustment of the donv lilfiJOllShlflg machine hay-r e polishing-lap mean- I gem in engagement with tr;

Iii

to polish the gem, and means for automatically pressing the gem against the lap with a progressively increasing pressure as the facet is worn away.

2L A gum polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap to polish the gcm and means for forcing the gem toward the lap with increasing pressure a the polishing proceeds.

:32. A gcnnpolishing machine having, in mmliinatioru a movable polishing-lap, a supporting arm. a gem-holding head adjustable ongitodinally of said arm parallel to the polishing-lap. means for locking said head in adjusted position on said arm, and means for autrnuatically moving said supporting arm liar k and forth in a line parallel to the surface of the lap while the gem is being iiicd.

gem-polishing machine having, in ccmibination. a moving polishing-lap, a gemhoidcr for holding the gem in contact with the lap. means for removing the gem from the lap. means having a member adapted to engage the lap in the path of the gem for causing said removing means to remove the gem from the lap at a predetermined stage in the polishing operation, means for mov ing the gem back and forth over the lap, and means having a member adapted to engage the lap in the path of the gem for causing said moving means to move the gem hac I and forth at a predetermined stage in the polishing operation.

2 A gem-polishing machine having in combination, a moving polishing-lap, a gemholder For holding the gem in contact with the lap means for rcnuiving the gem from the lap. means having a member adapted to engage the lap in the path of the gem for e asing said removing means to remove the gen: from the lap at a predetermined stage in the polishing operation. and means for adjas ing the distance of said member from the lap relative to the distance of'the geniholllw ti-om ihe lap.

2:3. arm -polishing machine hiring, in cenihimdion. a moving polishing-lap. a gemlihhisl' for holding a gem in contact with the lap. means for moving the gem back and ir 'th min the lap means having a member adapted to engage the lap in the path of the gem for causing said moving means to move the gem lrm'li and forth at a predetermined stage in the polishing operation, and means '1 miius 'ing the distance of said member from. the lap relative to the distance of the :lr ."ilfllll i From the lap.

' NE A gem polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap to POllSll thi- 559111 and means for forcing is gem toward the lap with increasing ressuro the pol hing pro eeds said last U L s mentioned means comprising a weighted lever.

21'. A gem polishing machine having in combination a polishing lap, means for holding the gem in engagement with the lap to polish the gem, means for forcing the gem toward the lap with increasing pressure as the polishing or grinding proceeds id means for checking or daniping the oovement of the gem toward the lap.

A gem polishing machine having in combination a polishing lap, a gem holder for holding the gem in contact with the lap, means for forcing the gem toward the lap with a gradually increasing pressure during the polishing. means for checking or damp ing the movement of the gem toward the lap a supporting means for the gem holder, means wherebv the gem holder may be adjusted on said supporting means to bring the gem onto different polishin bands of the lap, and means for reciprocatlng the gem laterally over the lap during the polishing or grinding of the gem.

29. A gem polishing machine having in combination a polishing lap, a gem holder for holding the gemin contact with the lap, a supporting means for the gem holder means whereby the gem holder may be adjusted on said supporting means to bring the gem onto dill'erent polishing bands of the lap and means for reciprocating the gem laterally over the lap durin the polishing or grinding of the gem.

30. A gem polishing machine having in combination a polishing lap, a gem holder for holding the gem in contact with the lap, means for forcing the gem toward the lap with a gradually increasing pressure during the polishing a supporting means for the gem holder and means whereby the gem holder may be adjusted on said supporting means to bring the gem onto difi'erent po1- ishing hands of the lap.

31. A em polishing machine having in combination a polishing lap, a gem holder for holding the gem in contact with the lap, means for automatically withdrawing the gem from the lap when the polishing operation has reached a predetermined stage, a supporting means for the gem bolder, means whereby the gem holder may be adjusted on said supporting means to bring the gem onto dill'erent polishing bands of the lap and means for reciprocating the gem laterally over the lap during the polishing or grindin ofthe gem.

32. A gem polishing machine having in combination a polishing lap a gem holder for holding the gem in contact with the lap, means for forcing the gem toward the lap with a gradually increasing pressure during the polishing a supporting means for the gem holder; means whereby the gem holder may be adjusted on said supporting means -for holding the gem in contact w th the lap,

means for forcing the gem toward the lap with a gradually increasing pressure during the polishing, means for automatically withdrawing the gem from the lap when the polishing operation has reached a predetermined stage and means for reciprocating the gem laterally over the lap during the polishing or grinding of the gem.

34. A gem polishing machine havingjn combination a polishing lap, 11. gem liolder for holding the gem in contact with thelap, means for forcing the gem toward the lap with a gradually increasing pressure during the polishing, and means for automatically withdrawing the gem from the lap when the polishing operation has reached a predetermined stage and a trip device for causing said withdrawing means to operate.

35. A gem polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap to polish the gem while permitting movement of the gem toward and from the lap, and damping means for checking or re' tarding the movement of the gem toward the lap.

36. A gem polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap to polish the gem while permitting movement of the gem toward and from the lap, damping means for checking or retarding the movement of the gem toward the lap, and means whereby the damping means does not retard themovement of the gem away from the lap.

37. A em polishing machine having in combinatlon with a polishing lap means for holding the gem in engagement with the lap to polish the gem while permitting movementof the em toward and from the lap, means for withdrawing the gem from the lap, and damping means for checking or retarding the movement of the gem toward the lap.

. 38. A gem olishingmachine having in combination with a polishing lap means for holding the gem in engagement with the lap to polish the gem while permitting movement of the gem toward and from the lap, means for withdrawing the em from the lap, damping means for checking or retarding the movement of the gem toward the lap and means whereby the damping means does not retard the movement of the gem away from the lap when with n by said withdrawing means.

39. A gem polishing machine having in combination, a rotary polishing lap, at supporting arm extending over th lap substantially parallel to the polishing surface thereof, a gem holder adjustable parallel to thepolishing surface of the lap on said arm to bring the gem onto different polishing bands of the lap, and means whereby the gem holder may be moved relatively to said arin twoard and away from the polishing surface of the lap in a line at right angles thereto.

40. A gem polishing machine having in combination, a rotary polishing lap, a. supporting arm extending over the lap sub stantiall parallel to thecpolishing surface thereof, a gem holder :1 justable on said arm to bring the gem onto different polislr ing bands of the lap, means whereby the gem holder may be moved toward and away from the polishing surface of the lap, and means for automatically withdrawin the gem from the lap when it has been p0 ished to a predetermined extent.

In testimony whereof I have afiixed my signature in presence of two witnesses.

CLYDE J. COLEMAN. Witnesses VICTOR D. Boner, WM. A. KELLY.

to bring the gem onto different polishing bands for the lap, and means for automatically witlnlrawing the gem from the lap when the polishing operation hasreached a predetermined stage and a trip device for causing said withdrawing means to. operate.

33. A gem polishing machine having in combination apolishing lap, a gem holder for holding the gem in contact with then- 1;.

means for forcing the gem toward thelap with a gradually increasing pressure during the polishing, and means for automatically lOllS in.Letters Patent No. 1,173,175.

withdrawing the gem from the lap when the polishing operation has reached a predetermined stage and a trip device forcansing said withdrawing means to operate.

35. A gem polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap to polish the gem while permitting movement of the gem toward and from the lap, and damping means for checking or retarding the movement of the gem toward the lap.

36. A gem polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap to polish the gem while permitting movement of the gem toward and from the lap, damping means for checking or retarding the movementofthe gem toward the lap, and means whereby the damping means does not retard the'movement of the gem away from the lap.

37. A gem polishing machine having in combination with a polishing lap means for holding the gem in engagement with the lap record of the case in the Patont Qfiice.

[any] to polishthe gem while'permitting movement oflthe em' towa'rd and from the lap, means for withdrawing the gem from the lap, and damping means for checking or retar-ding the the lap.

38. A em, 'polishing machine having in combination with a polishing lap means for holding'the gem in engagement with the lap to polish the gem while permitting movement of the gem toward and from the lap, means for withdrawing the gem from the movement of the gem toward lap, damping means for checking or retardmg the movement of the gem toward the lap, and means whereby the clamping means does not retard the movement of the gem away from the lap when with n by said with drawing means.

39. A gem polishing machine having in combination, a rotary polishing lap, a supporting arm extending over the lap substantially parallel to the polishing surface thereof, a gem holder adjustable parallel to thepolishing surface of the lap on said arm to bring the gem onto different polishing bands of the lap and means whereby the gem holder may be moved relatively to said arin' twoard" and away from the polishing surfaceflof the la in a, line at right angles tllELGtOp 40. A gem polishing machine having in combination, a rotary polishing lap, a sup porting arm extending over the lap sub stantiall parallel to the polishing surface thereof, a gem holder adjustable on saidv arm to bring the gem onto difierent polish.-- ing bands of the lap, means whereby the gem holder may be moved toward and away from the polishing surface of the lap, and means for automatically withdrawirrthe gem from the lap when it has been poiished to a predetermined extent.

In testimony whereof I have afiixed my signature in presence of two witnesses.

CLYDE J. COLEMAN.

\Vitnesses:

Vrcron D. Boner, WM. A. KELLY.

It is hereby certified that in Letters Patent No. 1,173,1i5, granted February 29, I 1916, upon the application of Clyde J. Coleman, of New Rochelle; New Yorky for an improvement in Gem-Polishing Machines, errors appear in the printed specificai. tion roquiringcorrection as tollo'ws; I ege 8 linesl97 and 1 20, claims 29 andv 31, beiorovthe word reciprocating insert the word independently; g 9, li 76- claim 39, for the word twoard? read toward; and tli'otv tho said Letters Patent should be read with these thoreinithat the some may conform to the Signed and'sealed this 11th a o; April, A. 1)., 1916.

R. F. w nrrnnn'nn; 4am 0 mm 01PM.

Qorrections in Letters Patent No. 1,173,175.

It is hereby certified that in Letters Patent No. 1,173,173, granted February 29, 1916, upon the application of Clyde J. Coleman, of New Rochelle, New York, for an improvement in Gem-Polishing Machines, errors appear in the printed Specification requiring correction as follows: Page 8, lines 97 and 1 20, 29 and 31, before the word reciprocating ineert the word independently; page 9, line 76', claim 39, for the word "twosrd read toward; and that the said Letters Patent should be read with these corrections thereinthat the same may conform to the record of the case the Patent0flice.

Signed and sealed this 11th day of April, A. D., 1916.

[smut] R. WHITEHEAD,

Acting 0mm ofPalmu. 

